On Tuesday, Microsoft released a new patch bundle that features three fixes for serious vulnerabilities of several Windows versions, which could be taken advantage of by remote attackers.

Among the seven identified vulnerabilities, three were considered to be "critical," three more were rated "important" and only one was catalogued as "moderate."

The three critical ones were found in Microsoft's Internet Explorer, DirectX and Bluetooth. The updates for the DirectX and Internet Explorer are taking care of flaws affecting pretty much all existing versions of Windows (including Windows 2000, XP and Vista). The Bluetooth error can only be found with XP and Vista.

The general opinion is that the Bluetooth issue (addressed by the MS08-030 patch) is the most serious one among the three critical problems. This error could give remote attackers the chance to introduce malicious code onto users’ computers; the only thing they would have to do is make use of the Bluetooth technology on an open network.

"If you're running Bluetooth on your computer, that means anybody else can hack your system and take control of it," Eric Schultze, CTO of Shavlik Technologies, said. "You don't have to do anything. Because you have Bluetooth turned on, someone can own your computer."

The other two critical vulnerabilities, affecting the Internet Explorer, are addressed by the MS08-031 patch. Once a malicious website is visited, because of the two errors, computers are left susceptible to remote code execution.

Although there haven’t been any reports regarding the exploitation of the aforementioned vulnerabilities, it is highly recommended that all users install the update as soon as possible.